I’m tired of my keys always jangling in my pocket, so I built a key-multi-tool out of a Crank Brother’s M5 bicycle tool. While I had the tool disassembled, I rearranged it so that the M3, M4 and #2 phillips were on the same side, which leaves room for five keys on the other side. It turns out other people had the the same idea. My keys still need cutting down since the key heads on the Medco keys are so large.